Earth-boring drill



llntented Sept.. 2?, mit@ JHN T. lmElDlPS, @F HUNTENGTN @LHRNE nnnrnmnonin'e Application filed July 2T?,

l This is a new application tiled in place ot in abandoned application, Serial Number 635,025, tiled January 8, 1924i, for earth looring drill.

This invention Arelates to earth boring drills, and is particularly directed to a drill of the rotary type having provisions for taking a core of the formation drilled through. i

'lt is an objectv of the present invention to provide a drill in which the drill body is provided with spiral boring and rearning cutters effecting a swirling of the ciroulat-1 ing mud water and promoting a rapid elevation of the boringsaway `irom the cutting blades in a manner which tends to prevent clogging of the cutters and Jfreezing oit the drill within the well bore, and further it isan object to provide spiral roaming cutters which, collectively, entend approximately a complete circle so as to insure a straight well bore.

A further object is to provide a core-drill having 'a core retaining means which is niain-1 tained in inoperative position during a boring operation and automatically moved to core retaining position upon elevation of the drill from the bottom'of the well bore. y

Another object is to provide a core drill having a longitudinally movable core-bit core-barrel, and a core retaining means operated by the movements oi said bit and barrel, with the bit 'restrained against rotary movement within the body and limited as to the extent of its longitudinal movements.

il further object is to providel a drill of y above character in which the core-bit and barrel may be interchanged with a central boring bit.

Various other objects and advantages will be more A.tully apparent from the following description of the accompanying drawings,

which Aform a part of this disclosure, and

l which illustrate a preferred Nforno ot embodinient of theinvention. @t the drawings: Fig. l is an elevation ot the drill in normal condition.

Fig. 2 is a bottom plan View. l Fig. 3 is an enlarged vertical section show- .is e plan section on line 8--8 oil bodyin place oi the core-bit and core barrel.

Fig. l is a bottom plan view, of the drill shown in llig. 9.

lll is an elevation'of ythe central boring bit shown in Figs. 9 and l0.

Figs. l2, 13, 1d are sectional views showing another form et structure, Fig. 12 being similar to Fig. d, Fig. 13 being similar to Fig. 3, and l ig. let being similar to Fig. 6.

is an elevation of the lower portion oi" the drill illustrated inFigs. l2 to 1d, said elevation being-partly in section to show more' clearly the bayonet-slot connection between the bore-bit and the drill body, all@ llig. isa plan section on line 16-16 ot Fig. l5.

particularly to Figs. l to 8, the complete device as e coredrill comprises a tubular drill body l which at its upper end is provided with a tapered screw-threaded pin 2 adapted to screw into a tubular subconnection 3 of suitable length and of the standard type having its upper end threaded to receive the drill-pipe 4. The core-barrel is carried by the core-bit, which will later be described, and entends upwardly through the body bore and the bore of the sub 3 and into the drill pipe 4, said barrel being of any desired length and consisting ot one or more sections joined by couplings 5. The upper end of said core-barrel is closed by a valve cage 6 providing a valve seat 7 and having a spring closedvalve 8 (3o-operating with said seat to prevent the circulating mud-water eol the valve against becoming fouled by mud or other substances.

The body 1 of the drill is provided with outwardly projecting circularly spaced reaming blades, there being two diametrically op-v posed long blades 9 extending nearly the entire length of the body, and two diametrically opposed short blades 10 extending only part way up the body.

All these blades terminate below the lower end of the body and are formed to provide transverse cutting edges 11 extending radially inward to the core-bit, (see Figs. 2 and The several cutting blades throughout their entire lengths are spiralled rearwardly and upwardly from the cutting edges 11, and collectively extend approximately entirely around the body, as is shown in Fig. 2. Thus there is provided a body having spiral boring cutters extending below the body and longitudinally extending upwardly along the body to provide reaming blades having nearly a full circular contact with the walls of the well bore, whereby, the boring action is made easier. the circulating mud-water is swirled to promote a thorough mixing of the borings with said circulating mud water, and av quick elevation of the borings is obtained. Further by reason of the angular disposition of the cutting blades their cutting edges 11 will be maintained sharper under wear than would perpendicular blades.

The cylindrical core-bit 12 has a shank 13 of a diameter adapting it to be inserted upwardly into the bore 14 of the body and to slide longitudinally therein, and has a shoul# der 15 providing an upthrust bearing limiting its upward movement.

The core-barrel 5 is screw threaded into the upper end of the shanky 13 and the bore of the shank down to a point 16 is of the same internal diameter as the core-barrel. From said point 16 downwardly to a point 17 the bore is slightly tapered to a smaller diameter, this form of bore providing relief for the core to prevent burning thereof.

Below the shoulder 15 the core-bit 12 is reduced in diameter and the lower end of said bit is formed to provide a plurality of radially disposed teeth 18 which are angled rearwardly, (see Fig. 1). The bases of the notches defining the teeth 18 are angled upwardly and outwardly from the point 17 to points within the space 19 formed by the reduced diameter portion ot the bit so that the. borings may easily discharge upwardly and outwardly intothe path of the cutting llade) and circulating mud-water, (see The body 1 is provided with four'circulation ports 20 communicating with the body bore 14 above the core-bit shank and discharging at the lower end of the body, one of `said posts discharging immediately in front of each respective cutting blade. (See Figs. 2 and 7.)

To form a. connection between the core-bit shank and the body which will prevent relative rotary movement and will at the same time permit longitudinal movement of the core-bit, I provide diametrically opposed key-ways 21 cut into the wall of the body bore upwardly from its lower end, and form on the shank 13 of the core-bitradially disposed keys 22 adapted to engage within said key' ways. (See Figs. 3, 4 and 7.)

The upward movement of the core-bit 12 is limited by the shoulder 15 engaging the lower surface of the drill body 1, and to limit the downward movement and to prevent the corebit and core-barrel from dropping from the drill, there are provided stop screws 23 which are screw-threaded into the bodyl and project into elongated grooves 24 cut in the wall ot' the shank 13 above the keys 22. (See Figs. 3 and 4.)

This construction provides a core-bit, and core-barrel which is longitudinally slidable within the drill body and is restrained against rotary movement therein, and it fur-IV ther provides means whereby the extent of longitudinal movement of the core-bit and core-barrel is limited and whereby they are prevented from dropping free of the body.

The longitudinal sliding movement of the core-bit within the body bore is utilized to manipulate a core retaining means adapted to engage and retain the core within the core barrel during the withdrawal of'the drill from a well bore. The core retaining means consists of a core-retainer 25 which is ositioned within an opening in the wall o the core-bit shank 13 and is provided with trunnions 26 having a pivotal engagement within lateral notches 27 in said shank on opposite sides of said opening. (See Fig. 3.) One end of the retainer 25 is of circular form and is adapted to nearly close the core-bit bore when the retainer is in normal horizontal position, (See Figs. 5 and 7) and its opposite end is extended beyond the trunuions to provide a nose 28 normally projecting between upper and lower cam shoulders 29, 30 formed on a block 31 removably inserted upwardly into a companion recess in the body and retained therein by a screw 32.

`With the parts in their normal positions as shown in Figs. 5 and 7, the weight of the core-bit and core-barrel will'maintain the lll) core-bit extended and the cam shoulder 29 lll lifrraaaa 3 its downward travel until. its lower surface engages the abutment shoulder on the corebit shank. During this independent movement of the drill body. the cam shoulder 29 engages the nose 28 of the core retainer 25, and moves said retainer upwardly out of the core-bit bore to 'the vertical position shown in Figs. 3 and 6, where it will remain during a drilling operation, and inwhich position the nose 28 projects slightly into the path of the cam shoulder 30.

yllhe drilling operation is continued until a core of desired length is obtained and the drill is then withdrawn from the well, and

during the iirst portion of such withdrawal ot the drill body, the cam shoulder will engage the nose 28 of the core retainer 25 and torce said retainer into engagement with the core, and if the core is trom relatively soft formation the retainer will be removed to the position illustrated in liig. 5 to completely bridge across the corefbit bore and support the core, but with a Core from relatively hard formation the retainer may only bite part way into the side of said core and come to a stop before the body has completed its independent upward movement, and in such event, as soon as the grip of the retainer upon the core is suliicient to overcome the weight of the core-bit and barrel they will then mvv" upwardly with the drill body as a unit.

lUpon withdrawal of the drill from the well bore, the stop-screws 23 and the retaining s rew 32 will be removed from the drill. body. he core-barrel 5 can then be unscrewed from the core-bit and the core-barrel sections uncoupled to facilitate the removal of the core. With the construction above described l have provided a core-drill having a longi-"` tudinallv translatable core-bit and barrel effective to project a core-retainer into the core receiving bore during a translation in' one direction and to positively retract such core retainer from'v said bore during a translation in a reverse direction.

ln Figs. .9 to 11, l have illustrated a modi.- hed arrangement in which a central boring bit is assembled in the body l in place of the core-bit and core-barrel, such a bit having the keys 36 tor engagement in the key-ways =21 of the body and grooves 37 which arel -wardly to correspond to the disposition of said blades, and is provided with'a. central water-way l0 communicating with the central bore lll of the body and discharging at the lower `end of. the bit, between the teeth. When the body i-s thus utilized in conjunction with the central bit 35 to form a boring drill, the block 30 previously described will not be assembled therein.

llt will be evident from the above that l have provided a drill body of more or less universal character which may be associated with the core-bit and core-barrel to torni a core-drill, or with the central boring bit to form only a boring drill.

lii Figs.- 12 to 16, there is illustrated another`form of construction ofboth the body and the core-bit'. ln this construction the shank 13a of the core-bit 12a has no uptlirustl shoulder and the body'lf has no stop-screws, the lreys 22a on the shank 13a in this instance engaging within bayonet grooves 2la formed in the peripheral wall of the body bore and providing rip-thrust and down-thrust shoulders 21b and 21, respectively, (see Fig. 15).l

ln inserting the shank 13a upwardly iiito the bore 14;a of the body 1a, the keys 22EL enter the vertical portions of the bayonet grooves 21a and the core-bit 12*I is then slightly rotated to bring saidkeys into the lateral portions of said grooves. A thrust-lblock 4l is then inserted upwardly into the vertical portion of each bayonet groove 21El and maintained in place by a screw 42 entering a companion orifice inthe body 1"l andscrew-threaded into said thrust block (see Fig. 13). The coreretainer 25El is of the same form as the core# retainer 25 previously described while its operating means is slightly changed in that instead of the block' 30 as previously ernployed, in this instance the upper cam slioulder 29a is formed directly oii the body 1tL and the cam shoulder 30a is in this instance the -inner portion ofa screw 43 carried by the body 1a in spaced relation to the shoulder 29a. (See Fig. 14.)

further construction change resides in the water-ways 2Oa which in this form of core-bit, are formed by longitudinally grooving the peripheral wall or' the core-bit shank 13a, (as shown in Figs. 13 and 16).

An advantage incident to the bayonet groove construction resides in the tact that in event ot wear of the grooves or keys. the trust blocks l1 can be renewed or replaced with others which are slightly wider to com-v pensate for such Wear.

The water-ways 20a, shown in Figs. 13 and 16, are ot advantage from a standpoint of cheapness `and ease ot manufacture vand further have a very decided advantage iii that with the core-bit removed from the body their entire lengths are exposed and may' easily be cleaned. y

While the mechanism herein illustrated tid nov

understood that I do not wish to limit the invention to the specific form of embodiment herein disclosed, for it is susceptible of em- -bodinient in various other forms all coming within the scope of the following claims.

l-laving described my invention, l claim:

l. ln a drill of the nature disclosed, a tubular body, a core-bit movably mounted within the lower end of the body-bore, and a core-retainer carried by the bit, the body having means adapted to be engaged by the core- 1`etainer during downward movment of the bit to inove said core-retainer to a lower core-retaining position.

2. ln a drill of the nature disclosed, a tubular body, a core-bit longitudinally slidable within the lower end or the body-bore and restrained against relative rotation therein, and a core-retainer carried by the bit, the body having means adapted to be engaged by the core-retainer during downward movement or" the bit to move said c0re- 'retainer to a core-retaining position.

3. ln a drill of the nature disclosed, a

tubular body, a core-bit longitudinally slidable within the lower end of the body bore and restrained against relative rotation therein` a core-retainer carried by the bit, the body having means adapted to be engaged by the core-retainer during downward movement of the bit to move said core re tainer to a core-retaining position, and means Jfor limiting the movement of the core-bit.

ln a drill of the nature disclosed, a tubular body provided with outwardly proiecting circnlarly spaced roaming cutters terminating below the lower end of the body with their lower ends 'formed to provide transverse cutting edges, a core-bit having a toothed lower end and a shank longitudinally slidable within the lower end of the body-bore, a corebarrel carried by the bit, and a core-retaining means moved to coreretaining position by the longitudinal downward movement of the bit, the shanli'. of said core-bit having longitudinally disposed peripheral grooves formino water ways coinniunicating with the bodyore above the bit shank and discharging at the lower end of the body.

5; In a. drill of the nature disclosed, a tubular body, a core-bit movably mounted within the lower end of the body-bore, and a core-reta`iner carried by the bit, the body having means adapted to be engaged by the core-retainer during downward movment of the bit to move said core-retainer to a lower core-retaining position, said tubular body being provided with outwardly proieeting` circularly spacedblades longitudinally ezeY tending to form reaming cutters, said blades being integral with the body and being extended below the lower end of the body with their lower ends formed to provide/transverse cutting edges.

6. In a drill of the nature disclosed, a tubular body, a core-bit movably mounted within the lower end of the body-bore. and a coreretainer carried by the bit, the body having means adapted to be engaged by the core 

